N. Oku et al., POTENTIAL USAGE OF THERMOSENSITIVE LIPOSOMES FOR MACROMOLECULE DELIVERY, Biochimica et biophysica acta. Biomembranes, 1191(2), 1994, pp. 389-391
Since transient swelling during phase transition of liposomes with hyp
er-osmotic internal aqueous phase may cause permeation of large molecu
les through the lipid bilayer, this type of liposomes can be useful fo
r delivering macromolecules. In fact, thermosensitive liposomes contai
ning an internal solution with osmotic pressure 2-fold higher than the
physiologic level and sized through 200-nm pore, released encapsulate
d macromolecules such as dextran (M, 144000) effectively when they wer
e incubated at 40-42 degrees C. These liposomes were stable in the pre
sence of serum compared to the liposomes with internal osmotic pressur
e more than S-fold higher than the physiologic level.